<?php
/* $Id$ */
namespace MCMS\Plugin;

use Mammut\DB\Sql\Expression\Parameter;

(defined ( 'MCMS' ) && (basename ( __FILE__ ) != basename ( $_SERVER ['PHP_SELF'] ))) or die ( 'ACCESS DENIED' );

/**
 * PlugIn base class.
 * 
 * This abstact base class provides helper methods for common plugin tasks.
 * 
 * @author Stefan Daurer <s.daurer@q-spot.org>
 * @package MCMS\System\Plugin
 */
abstract class PlugInBase extends \Mammut\StrictObject implements iPlugIn {
	
	/**
	 * Fetches the installed version from the database.
	 *
	 * @return string the version string or NULL if not installed
	 */
	protected static function getInstalledVersion() {
		$db = \MCMS\System::getInstance ()->getDB ();
		$sql = $db->select()->columns(['version'])->from('installinfos')->where(['type' => 'plugin', 'key' => new Parameter()]);
		$obj = $db->getObjectP($sql,[self::clazz()]);
		return empty($obj) ? NULL : $obj->version;
	}
}